With units mobile along a linear path, such as hoisting and conveying installations and also in the case of rotatable units such as radar installations or even computer tomographs, it is necessary to transmit electrical signals or energy between units mobile relative to each other. For the transmission of signals both contacting and non-contacting methods are known. The U.S. Pat. No. 5,208,581 discloses a method that permits the transmission of signals in a contacting manner, using a closed conductor. This method displays two decisive disadvantages. On the one hand, it is applicable only for closed arrangements in rotational symmetry and hence does not provide a solution for linear transmission systems such as those required for crane installations. On the other hand, this system displays very poor high-frequency properties in the event of signal feed from a mobile unit into the signal paths. The problem here resides in the aspect that a termination must be coupled at a position diametrically opposite to the feeding site via a second sliding-contact arrangement. The signal transmission operates perfectly only when both the feed coupler and the termination are appropriately coupled. In practical operation, this can be achieved only with very great difficulties when the usual sliding-contact arrangements such as gold spring wire or silver graphite carbons are used. The reason for this resides in the aspect that such contact systems have a contact resistance that may have a broadband noise character over a bandwidth of up to several mega Hertz. When now a series circuit (feeding site and termination) of two of such contact systems is required for a perfect function of the transmission system a low-noise transmission can be realised only with a very high expenditure. In this respect, non-contacting transmission techniques entail advantages, such as those described in the U.S. Pat. No. 5,530,422 and in the German patent specification DE 197 00 110. The first one of these transmission techniques uses a strip line for transmission whilst the second one of these transmission techniques operates on a conductor structure composed of a plurality of discrete dummy elements. This offers the advantages of very high noise suppression. In distinction from the conductor system mentioned first, both conductor systems are connected by their ends to form a closed ring. They are open and may hence be matched with any trajectory whatsoever. A respective termination element is provided on both ends of these conductor structures to form a reflection-free termination. The signals are fed invariably at a suitable site into the conductor structure. Hence, the signals are always transmitted from the conductor structure to a unit disposed for movement relative to the conductor structure. This systems presents, however, serious disadvantages in various applications. When, for instance, in the case of a linear transmission the signal transmission from mobile crane installations to a stationary unit is desired an antenna element must be mounted on that mobile crane installation, which element covers the entire length of the displacement path. This means that an antenna carrier of 50 m in length, for example, must be mounted at the bottom of the crane installation. In other fields of application, e.g. in computer tomographs, the conductor structure is applied on a mechanical slip ring that rotates together with the rotating part. Hence, data transmission from the rotating part to the stationary part is possible without any problems whilst a transmission in the opposite direction requires an additional ring for receiving a stationary conductor structure. Specifically in the field of computer tomographs, this cannot be realised for reasons of costs. The term “conductor structure” will be used in the following as a generic term encompassing structures in which electromagnetic waves can propagate, e.g. arrangements composed of dummy elements, strip lines or other conductor systems.